Mazda 121 - Rough Idle;Engine Stalls at Idle - after Warm-Up

TROUBLESHOOTING GUIDE F
10 ROUGH IDLE/ENGINE
STALLS
AT IDLE
-
AFTER WARII.UP
DESCRIP.
TION
.Engine
runs normally al idle during wam-up but
engine stalls
or vibrales
excessively afler
warm-up
ITROUaLESHOOTTNG
HINTSI
O)
rdle
speed contror svslem mallunction
@
Air/Fuel mixture loo lean
.Low
fuel line
pressure
.
PCV vatve stuck
(open)
@
ArlFuel mi(ure too nch
.Fuel
injecl on control mal,unclion
(Corection
ior coolanl temperature)
@
Poor ignilion
O
Low engine compress on
INSPECT|oiT
ACTION
1 ls 00" displayed on
Self-Diagnosis Checker
with ignilion
switch ON?
e
page
F-67
llalluncfion Code ilo. displ.yed
Check lor cause Geler lo so€cilied
ch€ck
sequence)
(?
page
F-m
"8a"
tlashes
Check ECU termina lF vollage c7
page
F-114
Volreg€: Approx. r2V
(lgnition
switch
ON)
+
li OK, replace
ECU
rz page
F-112
+
ll noi
OK, check wiring bolween
ECU and SellDiasnosis Checker
2 Are ECU lerminal
voltages OK?
(Especially
1K,
2M, 20 and 20)
F
page
F-112
Check
ior
caus€ c7
page
F-115
F-117
F-r9
3 Disconnect highlension lead
at dle; does en-
glne
speed d€crease
equally al al cylinders?
Go to Slep 10
ls ihere air leakage
ol intake arr system com-
5 ls air cleaner
element cl€an?
e
page
F-62
No R€place alr cleaner element
6 lurn thronle adjusling
screw c,
does
idle
condilion
improve?
AIFFLOW SENSOR
I
-ffiqf l";;I
Adjust idle
speed
.?
page
F-62
No Relurn
lhrottle
adiusling screw to
its
original
positlon,
and
go
to next slep
=.\\\
/
F-33